<!DOCTYPE html>
<html>
<head>
	<meta charset="utf-8">
	<meta http-equiv="X-UA-Compatible" content="IE=edge">
	<title></title>
	<link rel="stylesheet" href="">
	<style type="text/css" media="screen">
	/*不定宽高的水平垂直居中*/
		.box {
			width: 300px;
			height: 300px;
			border: 1px solid red;
			display: table-cell;
			text-align: center;
			vertical-align: middle;
		}
		.wrap {
			width: 100px;
			height: 100px;
			border: 1px solid red;
			vertical-align:middle;
			display:inline-block;
		}
	</style>
</head>
<body>
	<div class="box">
		<div class="wrap">
			
		</div>
	</div>
</body>
</html>